1. Field of the Invention
The present invention relates to an image display apparatus which is represented by a liquid crystal display apparatus, and electronic equipment equipped with an image display apparatus, and in particular, to a computer system.
2. Background Art
The diffusion of personal computers (hereafter, PC) is remarkable, and the activities in the office, which are performed without using PCs, now are no longer considered. In addition, there is also a case that both a desktop PC, installed in an office, and a notebook PC, excellent in portability, are used as PCs.
Since being excellent in portability, a notebook PC is frequently used in places other than an office. Since illumination is fully provided when the notebook PC is used in an office, it is possible to secure sufficient luminosity on a keyboard that is the input means of the notebook PC. However, sufficient luminosity may be unable to be secured when used in places other than an office. For example, it is the case that a notebook PC is used in an airplane. In the airplane that is performing a night flight, when people around are sleeping and an overhead lamp provided in the airplane is used, a trouble may happen for the people around. Therefore, assuming such a situation, it is desirable to equip the notebook PC with an illumination light that can illuminate a keyboard.
A computer that can meet this request is disclosed in Published Unexamined Japanese Patent Application Nos. 6-83479 and 8-76882.
A portable computer 100 disclosed in Published Unexamined Japanese Patent Application No. 6-83479 is shown in FIG. 12. This portable computer 100 comprises a keyboard unit 101 equipped with keys 102 in a top face, a display unit 104 equipped with a display screen 103 in a top face side, and support means 105 supporting the display unit 104 over the keyboard unit 101. The display unit 104 is arranged so that it can be seen from a top against the keyboard unit 101 with the support means 105 configured by a linkage or a support. A lamp 106 illuminating the keys 102 on the keyboard unit 101 is provided in an undersurface side of the display unit 104.
A portable computer 200 disclosed in Published Unexamined Japanese Patent Application No. 8-76882 is shown in FIG. 13. The portable computer 200 consists of an operation unit 201 equipped with a keyboard 202, and a display 203 equipped with a liquid crystal panel 204. A backlight unit consisting of a fluorescent lamp 205, a light guide plate 206, and a passive reflector 207 is provided in a back surface of the liquid crystal panel 204. In addition, a passive reflector 208 and a condenser lens 209 condensing light reflected from the passive reflector 208 on a keyboard 202 are provided near the fluorescent lamp 205.
Since a keyboard can be illuminated effectively even if the portable computer 100 disclosed in the above described Published Unexamined Japanese Patent Application No. 6-83479 or the portable computer 200 disclosed in the above described Published Unexamined Japanese Patent Application No. 8-76882 is used in the darkness of an airplane, there is hardly a possibility of troubling people around.
A portable computer such as a notebook PC receives the supply of power from external commercial AC power or a built-in battery. In a place, which has a commercial AC power, like an office, the portable computer receives the supply of power from the commercial AC power through an adapter. In a place without the commercial AC power, the portable computer receives the supply of power from the built-in battery. At the time of riding on a conveyance such as an airplane and using a portable computer, the portable computer will receive the supply of power from the built-in battery. However, with a present built-in battery, a portable computer cannot be used over a long time. For example, the power of a built-in battery will be consumed by the use in about 2 to 3 hours.
When a lamp 106 for illuminating the keys 102 is newly provided like the portable computer 100 disclosed in Published Unexamined Japanese Patent Application No. 6-83479, the power for turning on a lamp 106 is needed. In case the lamp 106 is turned on in an airplane, a built-in battery will be asked for the power. Therefore, the consumption of the built-in battery will become quick.
In the case of the portable computer 200 in Published Unexamined Japanese Patent Application No. 8-76882, a fluorescent lamp 205 that is a light source of a liquid crystal panel is asked for light illuminating the keyboard 202. That is, since the light source for illuminating the keys 102 is not newly provided like Published Unexamined Japanese Patent Application No. 6-83479, the problem that power dissipation increases does not arise. However, since the portable computer 200 disclosed in Published Unexamined Japanese Patent Application No. 8-76882 radiates light to the keyboard 202, additional elements, which are originally unnecessary for the liquid crystal panel 204, such as two passive reflectors 207 and 208, and a condenser lens 209 are needed. An additional element raises cost while complicating structure. In addition, since it is obliged to secure a space for arranging the additional element, it will be contrary to a common requirement, that is, miniaturization.
In view of the above situation, a subject of the present invention is to provide an image display apparatus that can illuminate input means such as a keyboard without adding a new element and moreover increasing power dissipation. Moreover, another subject of the present invention is to provide electronic equipment and a computer system each of which is equipped with such an image display apparatus.
A feature of the present invention relates to a display apparatus characterized in having a display panel for displaying an image, a light source for supplying light to the display panel, and a flat-surface lighting surface member which has a lighting surface emitting light, radiated from the light source, as flat-surface light while being arranged with the display panel. A housing contains the display panel, the light source, and the flat-surface lighting surface member. The housing further includes a window through light passes the flat-surface lighting surface member and leaks to the outside.
Another feature of the present invention provides a liquid crystal display apparatus that includes a liquid crystal display panel for displaying an image, a light source for emitting light for image display, and a light guide plate that has a front surface and a back surface. The liquid crystal display panel is arranged so that it is on the front surface side of the light guide and is used for leading light, emitted from the light source, to the liquid crystal display panel. A frame that holds the liquid crystal display panel, the light source, and the light guide plate has an optically transparent area that transmits light emitted from a back surface of the light guide plate.
Still yet another feature of the present invention provides an electronic equipment comprising an input operation unit, where operation keys are provided, and a display unit. The display unit comprises a display panel displaying an image by receiving the radiation of light, a light source for supplying the light, and an irradiating plate for radiating the light that is being emitted from the light source to the display panel, and illuminating the input operation unit by a part of the light radiated from the irradiating plate.
Furthermore, another feature of the present invention provides a computer system having an operation unit equipped with a keyboard as input means, a liquid crystal panel displaying an image, a backlight unit supplying light to the liquid crystal panel, and a frame that holds the liquid crystal panel in a front surface side and the backlight unit in a back surface side. The backlight unit includes a light source, a light guide plate that receives light emitted by the light source and emits flat-surface light from its own front surface side toward the liquid crystal panel, and a passive reflector which is arranged in a back surface side of the light guide plate and has translucency. A window that is formed in the back surface side of the frame leaks light being transmitted in the light guide plate and the passive reflector.
Therefore, another future of the present invention provides a computer system having an operation unit equipped with a keyboard as input means, a display panel displaying an image depending on contents of an operation of the operation unit, a light source emitting light for image display in the display panel and for illuminating the operation unit, and an optical distributor that receives light emitted from the light source, and distributes light for illuminating the operation unit, and for the image display.
Therefore, still another feature of the present invention provides a computer system having an operation unit equipped with a keyboard as input means, and a display unit equipped with a first surface displaying an image depending on contents of an operation in the operation unit and a second surface facing the first surface, and the light source supplying light for image display, wherein a part of light supplied from the light source is radiated toward the first surface, and another parts leak from the second surface to illuminate the operation unit.
Various other objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views.